And isotropy of the universe. Okay that only helps on the really large and really small scale
But the fact that regular Newtonian physics works so well is because it's aggregated over so many particles, we are so far from the froth of the quantum world, that when designing a bridge, we can assume things, and those assumptions will be valid almost everywhere.
There's no need for correcting for local variations that are needed in econ. Or from a different perspective the fact that we have simple laws in physics, and chemistry, and engieering, is because we are only considering/using a _very_ limited part of the whole universe.
The classic CH4 + 2 O2 = CO2 + 2 H2O is a gross oversimplification, because there are a few dozen other things going on at the same time, and NASA/SpaceX/BlueOrigin has to consider those when they burn in an athmosphere. But since we rarely encounter these problems we don't often find ourselves lacking enough data to fit a better theory. (But of course that's what's happening in post standard model physics, or in cosmology, or in trying to design fusion plants, we are very early in magnetohydrodynamics, and even designing a better corrosion resistant material for use in molten salt reactors is a challenge.)
So, just as we have models for ant ecologies we have for economics of states/countries, but just as neuroscientists have trouble figuring out how exactly an ant works and when does what and where ants will go to forage next economists have trouble predicting when the next crash will happen. (See also bee hive collapse syndrome, we still don't know what causes it, yet there's a lot of hives and we could even do experiments with them easily.)